ALAMO-HUECO RANCH — The boys wake before dawn, eat sausage and biscuits in the cookhouse and saddle their horses at first light. James Hurt is 12, a month away from becoming a teenager. His brother, David, is 11. They wear Wrangler shirts, jeans and cowboy boots and move quietly in the dark corral, lit by a single bulb. It’s an autumn Sunday in 2017.